Could not connect to Ambari log-on screen

[#1]

During a recent installation at a customer site, on an 8 Node cluster, and after successfully going through the prep stages, and successfully installing and restarting Ambari server, was not able to connect to Ambari log-on screen.

[#2 · Accepted solution]

Symptoms:

Ambari-server.out logs a warning regarding A HTTP GET method :

WARNING: A HTTP GET method, public javax.ws.rs.core.Response org.apache.ambari.server.api.services.StacksService.getStackVersions(java.lang.String,javax.ws.rs.core.HttpHeaders,javax.ws.rs.core.UriInfo,java.lang.String), should not consume any entity ...

The Fix:

Only after changing client.threadpool.size.max=<number of cores> in /etc/ambari-server/conf/ambari.properties

to match the number you get from running nproc on the linux command line, then restarting Ambari-server, would the

Ambari logon screen show.

At Linux shell command line run

  1. [root@SERVERNAME ~]#  nproc

Write down the number of core resulting from running nproc. Ex.g: 56

  2.  [root@SERVERNAME ~]#  vi /etc/ambari-server/conf/ambari.properties

Find client.threadpool.size.max=<number of cores>, then change to client.threadpool.size.max=56

  3.  [root@SERVERNAME ~]#  ambari-server restart

That should resolve this particular issue on on REHL 7.X.

Referencing AMBARI-9776;